Nguyen Dinh Giang Nam * , Goto Akira and Osawa Kazutoshi

* Corresponding author (ndgnam@ctu.edu.vn)

Main Article Content

Abstract

In this study, the three-factor rheology model was applied to simulate land subsidence associated to the groundwater decline in the urban area (Can Tho) and the coastal area (Soc Trang) of the Mekong Delta (of Viet Nam). The considered three factors are: (1) the elasticity coefficient; (2) the viscosity coefficient of the Voigt part; and (3) the viscosity coefficient of the Damper part, were calibrated to get the matching with limited observed values. As the results, the long-term transient simulation in the period of 2000-2013 showed the land subsidence rate in Can Tho city was around 2.6 cm/year. For the coastal area, transient simulation showed the cumulated subsidence for the period of 1994-2014 was 65 cm which means around 3 cm per year. To maintain the groundwater pumping under future rainfall condition, another 60 cm of land subsidence was expected over the next 21 years in the coastal area. To understand the subsidence under increase in pumping (1.8% per year), the cumulative land subsidence in the period of 2014-2035 was estimated around 71.4 cm at the coastal area of Mekong Delta.
Keywords: Land subsidence, Mekong Delta, Rheology model, Three factors

Article Details

References

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